The Wide-Field Infrared Explorer, or WIRE, began spinning faster than planned after separating from its launch vehicle, and ground crews have declared an emergency.

"It is not known at this time what specifically caused the orientation malfunction on the spacecraft and a further investigation ... is being done to assess the problem," a NASA statement said.

WIRE left the Earth aboard a Pegasus-XL rocket. Rocket builder Orbital Sciences Corp.'s L-1011 jet carried the three-stage rocket and released it over the Pacific Ocean at an altitude of about 40,000 feet at 7 p.m. PCT (3000 GMT Friday).

The 561-pound (254-kilo) space probe, designed to orbit the Earth 340 miles (550 km) high and circle the planet every 90 minutes, is part of NASA's Origins Program.

If WIRE works as planned, Goddard Space Flight Center in Greenbelt, Maryland, will control the flight, while The California Institute of Technology in Pasadena, California, will receive the data from the spacecraft.

NASA devised the mission to help researchers learn how and when galaxies have formed and evolved. The
spacecraft's 12.5-inch (30-cm) telescope will scan the universe, focusing on extremely bright star clusters
known as starburst galaxies, which produce new stars at 10 times the rate of typical galaxies.

WIRE is expected to detect at least 50,000 galaxies, NASA said.

The search will go as far back as the origins of the heavens. "WIRE also will conduct a search for
powerful, dusty quasars in the very early universe, shortly after the Big Bang," Hacking said.

But it may unravel some mysteries closer to home. WIRE could provide some answers on how the universe
reached the critical point where it formed stars like the sun and planets like the Earth.

Besides the origins of stars, NASA hopes WIRE will shed light on the origins of life. "In these
protoplanetary disks of dust and gas of other stars where planets are forming today, are there temperature
regimes in the comfort zone where planets like the Earth might form and have temperatures that would be
conducive to life," said Ed Weiler, director of the Origins Program.

WIRE should remain cool over the course of its daunting, four-month mission. As heat from the
craft could distort the light images it detects from space, NASA enclosed the telescope in a hydrogen
cooling system to keep the instruments below minus-436 degrees Fahrenheit (minus-260 degrees Celsius).

WIRE is also part of NASA's Small Explorer (SMEX), a series of highly focused and relatively inexpensive space science missions.